[ARM] 3569/2: netX: driver for XMAC/XPEC engines

Patch from Sascha Hauer

The netX processors have generic network bitstream engines (XMAC/XPEC).
This driver adds support for firmware loading and start, stop, reset
commands.

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>